The invention relates to a method for producing gear wheels, specifically transmission gear wheels.
In vehicle transmissions and in transmissions for aircraft engines higher power densities with smaller dimensions and lower overall weights are increasingly being required for the transmissions. As a result, the load on the gear wheels used in the transmissions is increasing. In order to be able to subject the gear wheels to greater loads, new design principles for the gear wheels are required. Such high-performance gear wheels which can be subjected to high loads have, for example, new involute shapes or stiffening ribs running in the circumferential direction. Such high-performance gear wheels cannot, however, be manufactured with the necessary accuracy using the production methods known from the prior art such as milling, broaching, grinding, honing and lapping. Specifically, the manufacture of gear wheels which have reinforcing ribs running in the circumferential direction using the manufacturing methods known from the prior art presents serious difficulties.
With this as the point of departure, the problem for the present invention is to create a novel method for manufacturing gear wheels, specifically transmission gear wheels.
In accordance with the invention, the method comprises at least the following steps a) preparation of a base body for a gear wheel, b) electrochemical processing of the base body through a precise electrochemical machining process (PECM process), in which several recesses running between the teeth are made simultaneously by electrochemical means to produce the teeth of the gear wheel.
With the present invention it is provided for the first time to produce gear wheels with the help of a precise electrochemical machining process. This makes it possible to manufacture high-performance gear wheels with stiffening ribs and/or new involute forms with the necessary accuracy. This makes it possible to increase the forces which can be absorbed by the teeth of a gear wheel and to use this potential to reduce the dimensions of the gear wheel.
Preferably a base body is prepared for the gear wheel which is already preformed or preshaped.
In accordance with an advantageous refinement of the invention, several working electrodes are moved simultaneously through a relative radial motion between the base body and the particular working electrode into the base body.
In accordance with an alternative advantageous refinement of the invention, a working electrode which has a cross-sectional contour of the gear wheel to be manufactured is moved into the base body as the result of a relative axial motion between the base body and the working electrode.
Preferred refinements of the invention can be derived from the description hereinafter.